<template>
  <div class="testTracking">
    <video
      id="video"
      width="1000"
      height="700"
      preload
      autoplay
      loop
      muted
    ></video>
    <canvas id="canvas" width="1000" height="700"></canvas>
    <div class="buttonDiv">
      <button type="button" @click="submit" style="font-size: 3vw;">提取照片</button>
      <button type="button" name="button" @click="checkFace" style="font-size: 3vw;">检测人脸</button>
      <button type="button" name="button" @click="getCompetence" style="font-size: 3vw;">
        打开摄像头
      </button>
      <button type="button" name="button" @click="de" style="font-size: 3vw;">停</button>
    </div>
  </div>
</template>

<script>
require("tracking/build/tracking-min.js");
require("tracking/build/data/face-min.js");
require("tracking/build/data/mouth-min.js");
require("tracking/examples/assets/stats.min.js");
export default {
  name: "testTracking",
  data() {
    return {};
  },
  methods: {
    checkFace() {
      var video = document.getElementById("video");
      var canvas = document.getElementById("canvas");
      var context = canvas.getContext("2d");

      var tracker = new tracking.ObjectTracker("face");
      tracker.setInitialScale(4);
      tracker.setStepSize(2);
      tracker.setEdgesDensity(0.1);

      this.trackerTask = tracking.track("#video", tracker, { camera: true });

      tracker.on("track", function (event) {
        if (event.data.length <= 0) {
          return;
        }
        context.clearRect(0, 0, canvas.width, canvas.height);
        event.data.forEach(function (rect) {
          context.strokeStyle = '#a64ceb';
          context.strokeRect(rect.x, rect.y, rect.width, rect.height);
          context.font = '11px Helvetica';
          context.fillStyle = "#fff";
          context.fillText('x: ' + rect.x + 'px', rect.x + rect.width + 5, rect.y + 11);
          context.fillText('y: ' + rect.y + 'px', rect.x + rect.width + 5, rect.y + 22);
        });
      });
    },
    submit() {
      let that = this;
      let canvas = document.getElementById("canvas");
      let context = canvas.getContext("2d");
      let video = document.getElementById("video");
      context.drawImage(video, 0, 0, 1000, 700);
      canvas.toBlob((blob) => {
        // axios.post({ faceUrl: URL.createObjectURL(blob) }).then((res) => {
        //   console.log("上传成功");
        // });
        var reader = new FileReader();
        reader.readAsDataURL(blob);
        console.log(reader);
      });
    },
    getCompetence() {
      var _this = this;
      this.thisCancas = document.getElementById("canvas");
      this.thisContext = this.thisCancas.getContext("2d");
      this.thisVideo = document.getElementById("video");
      // 旧版本浏览器可能根本不支持mediaDevices，我们首先设置一个空对象
      if (navigator.mediaDevices === undefined) {
        navigator.mediaDevices = {};
      }
      // 一些浏览器实现了部分mediaDevices，我们不能只分配一个对象
      // 使用getUserMedia，因为它会覆盖现有的属性。
      // 这里，如果缺少getUserMedia属性，就添加它。
      if (navigator.mediaDevices.getUserMedia === undefined) {
        navigator.mediaDevices.getUserMedia = function (constraints) {
          // 首先获取现存的getUserMedia(如果存在)
          var getUserMedia =
            navigator.webkitGetUserMedia ||
            navigator.mozGetUserMedia ||
            navigator.getUserMedia;
          // 有些浏览器不支持，会返回错误信息
          // 保持接口一致
          if (!getUserMedia) {
            return Promise.reject(
              new Error("getUserMedia is not implemented in this browser")
            );
          }
          // 否则，使用Promise将调用包装到旧的navigator.getUserMedia
          return new Promise(function (resolve, reject) {
            getUserMedia.call(navigator, constraints, resolve, reject);
          });
        };
      }
      var constraints = {
        audio: false,
        video: {
          width: this.videoWidth,
          height: this.videoHeight,
          transform: "scaleX(-1)",
        },
      };
      navigator.mediaDevices
        .getUserMedia(constraints)
        .then(function (stream) {
          // 旧的浏览器可能没有srcObject
          if ("srcObject" in _this.thisVideo) {
            _this.thisVideo.srcObject = stream;
          } else {
            // 避免在新的浏览器中使用它，因为它正在被弃用。
            _this.thisVideo.src = window.URL.createObjectURL(stream);
          }
          _this.thisVideo.onloadedmetadata = function (e) {
            _this.thisVideo.play();
          };
        })
        .catch((err) => {
          console.log(err);
        });
    },
    de() {
      // 停止侦测
      this.trackerTask.stop();
      // 关闭摄像头
      this.trackerTask.close;
    },
  },
  destroyed() {
    // 停止侦测
    this.trackerTask.stop();
    // 关闭摄像头
    this.trackerTask.closeCamera();
  },
};
</script>

<style lang="scss" scoped>
.testTracking {
  height: 100vh;
  width: 100%;
  position: relative;
  > * {
    position: absolute;
    left: 0;
    right: 0;
    margin: auto;
  }
  video,
  canvas {
    top: 0;
  }
  .buttonDiv {
    bottom: 10px;
  }
}
</style>
